A brief questionnaire to assess competitiveness in sports was developed and analyzed psychometrically. The items in this questionnaire were developed on the basis of a review of the literature on achievement motivation theories in sports (content validity). An experiment was then conductedin which the participants were exposed to a competitive game. The competitive game experiment was used as external criteria to evaluate the degree of the competitiveness trait degree in competition (empirical validity). The experiment and psychometric study included 153 university students (43. 8% women and 56. 2% men) between the 19 and 32 years of age (an average 22. 9 years old, DT=2,5). The factorial analysis supported the construct validity and identified two independent dimensions: Motivation for success (a = 66) and Motivation to avoid failure (a = 66), the reliability of the two subscales was acceptable. The questionnaires concurrent, discriminant and predictive (sensitivity 72. 6% and specificity 50. 7%) criteria validity was also identified, bearing in mind the results of the competition and the subjective self-evaluation of the degree of competitiveness. In summary, the questionnaires psychometric indicators confirm the questionnaires construct validity, reliability and empirical validity. Gender differences and an age effect on motivation for success were observed.